We were running our Dungeon World campaign, and the time came to confront the goblins about their evil ways and interrogate them for what they knew. At this point, we hit a snag; how can we know if any of our intrepid heroes of yore speaks Goblin?

We couldn't find any kind of 'Languages' information, nor could we find any 'Knowledge' skills or anything that could seem relevant. In attempting to keep to the spirit of the game, we handwaved it; the Goblin adopted a superior air and condescended to speak "Common" for the 'uneducated Humies'.

Is there a section of the rules regarding what characters may know or speak?

Languages are something that have come up in our Dungeon World campaign a lot. There's no language list or anything in the game because that kind of thing isn't usually much fun (at least, not to us - you could very easily have a list and say "for each + to your INT, add one to your list).

What I do, when I GM, is just ask questions. When I say "the little brown skinned lizard-creature blithers at you in its strange language" the PCs will often say "Is that a Kobold?" and I'll say what the truth demands: "yes, of course!" and they'll ask "Do I speak Kobold" and I'll ask questions and build on their answers by saying "I don't know, do you?" and if they say yes, the follow-up is often "well, that's cool, where'd you learn that?" and we'll digress if necessary, or not, and we'll come back to the game.

You learn things about the characters and if they players want to be MASTER OF ALL LANGUAGES you've managed to get them to explain how that happened and what brought them here. That's part of what being a fan of the characters is about.

Yes, this. DW (and AW before it) is about not trying to limit the PCs when no move is involved, so that lots of interesting stuff happens. Ask questions to explain these liberties and then use the players' explanations to make the setting and their lives even more interesting.
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SevenSidedDieAug 1 '12 at 18:23

I'm going to throw this out here because I just wrote these moves yesterday for my own game:

If you are a Bard, Cleric, a Wizard or a noble, you are educated, but have no trade skill. You can, read and write well in the local language, trade pidgin, and an ancient language. What is the ancient language called? What else can you say about it?

For my group's elf wizard:

You are educated, but you have no trade skill. You can also, read and write in Elvish, Ancient Elvish, just fine. You can speak the local language and pidgin just fine, but write them poorly.

You can keep your language skills as is, OR roll +INT: On a 10+ pick two (you can pick the same one twice), on a 7-9 pick one:
• you are also fluent in another language. Name it.
• you can choose two more languages you read, speak and write. Name them.
• you gain no new language skills, but your current language skills are excellent, poetic, etc.
On a miss, your writing skill is poor.

If you are a commoner Thief or Fighter, etc., you have a trade skill if you want one. If so, what is it?

Commoners/the lesser educated: You can speak pidgin and the local language. Roll +INT: On a 10+ roll on the table above or choose 3:
• you can read and write pidgin. Tell us how you learned it.
• you can read and write the local language. Tell us how you learned it.
• you can speak another language. What is it? Tell us how you learned it.
• you can read and write another language. What is it? Tell us how you learned it.On a 7-9, choose one:
• you can read and write one of the languages you speak. Which one?. Tell us how you learned it.
• you can read and write only poorly in both pidgin and the local language. Tell us how you learned them.
• you can speak another language or read another language. What is it?
On a miss, pick one:
• you can read a little and make your mark, in pidgin or the local language, but can't write much beyond that.
• you can't read or write at all, but you can choose another trade skill.

Admittedly, it is a bit convoluted. So, before I presented these moves to my group, I also allowed them to opt out and just tell me what languages the know, which I think is fine, but if they choose to roll, they should keep it.

This is just part of the fiction. They can learn a language in the game if they study one or have good exposure to one.